Velocity measuring device



1943- r c. L. ROBINSON 2,310,546

VELOCITY MEASURING DEVICE Filed May 5, 1940 2 Sheets- Sheer. 1

' 53 I 52 i g 1 I .:'IIIIIII H, M V I rllllllllllllllllllln Feb. 9, 1943. c. L. ROBINSON VELOC I'IY MEASURING DEVI CE Filed May 3, 1940 2 Sheets-Sheet 2 Patented Feb. 9, 1943 UNITED STATES Ni" OFFICE 2,310,546 VELOCITY MEASURING DEVICE Claude L. Robinson, Michigan City,

Consolidated Instruments to Michigan City, Ind

1116., assignor Corporation,

., a corporation of Indiana Application May 3, 1940, Serial No. 333,206 Claims. (Cl. 73205) The 0 nd A further object of the duction of such a system which is especially objector the invention is the proiuction of such a speed indicator constructed ticularly pointed out in the appended claims.

In the drawings wherein like reference characters indicate like or corresponding parts:

Fig. l is an elevational invention as boats or the like;

Fig. 2 is a sectional view through the equal izing unit taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is an end elevational view of the pressure differential generating foot illustrated in Fig. 1;

Fig. 4 is an elevational sectional View of a pressure differential generating device of the socalled obstruction to the flow type for use in pipe lines or the like for measuring the rate of fioW of fluid therein;

Fig. 5 is a front elevational view of a unitary speed indicator for boats embodying the present invention;

Fig. 6 is a vertical sectional view taken along the line 6-45 of the device illustrated in Fig. 5; and Fig. 7 is a sectional view taken substantially on the line 1-! of Fig. 6.

The present invention is particularly adapted to be used for ditions causing sitating numerous and sometimes complicated adjustments.

This foot is provided with a threaded stem 3 which extends through the bottom 2 a suitable nut leakage between and is held in place by means of 4, gaskets 5 and 6 preventing the parts, and a Washer 1 being interposed between the nut 4 and gasket 6. The outer end 3 of the foot is constructed in the form of a longitudinally extending plate and is provided with passages H and |2, respectively. These passages terminate in ports l3 and M, respectively, the port l3 being forwardly positioned and the port |4 rearwardly positioned with respect to the boat hull, the normal motion of the boat being in the direction of the arrow. The action of this foot in the water is similar to that of the up and down stream Pitot tube and is familiar to' those skilled in the art.

An equalizing or balancing unit, designated generally by the numeral 2|, is operatively. connected by means of tubing 22 and 23 with the foot I. The unit 2| is provided with a pair of chambers 24 and 25, the latter being formed by concentric tubing 25 and 21 of suitable material, preferably transparent, and top and bottom plates 23 and 29. The latter are of similar shape and are securely maintained in engagement with the tubing 25 and 21 by tie rods 3| extending between the two plates and secured by cap nuts 32 so that the plates are drawn toward one another, securely clamping the tubing 26 and 21 in position. Gaskets 33 and 34 interposed between the ends of the end plates 28 and 29 effectively render the chambers 24 and 25 fluid tight. The bottom plate 29 is provided with ports 35 and 35 communicating with the chambers 24 and 25. The connecting tubing 22 and 23 connects with the ports 35 and 35, the tubing terminating in couplings 31 which are engageable with nipples 38. Thus, the port |3 of the tool: is operatively connected through tubing 22 with the chamber 24 while the port I4 is similarly connected I the chamber 25. The unit 2| is preferably positioned substantially at normal water lever so that the chambers will be partially filled with water when the boat is at rest and the system under static water pressure. The upper plate 23 is provided with ports 39 and 4| similar to the ports 35 and 36. Flanges 42 on the plates 28 and 29 provide means for mounting)the unit to any suitable supPQrt.

An indicating device designated generally by the numeral 43 is connectedwith the ports 39 and 4| by tubing 44 and 45, the latter being secured to the plate 28 by couplings 31' and nipples 38'. The indicator illustrated comprises an actuating unit having a housing 46 divided into chambers 41 and 48, the latter being separated by a flexible diaphragm 4 9. Tubing 44 connects chamber 24 of the unit 2| with the chamber 4'! of the indicating device, while tubing 45 connects chamber 25 of the unit 2| with the chamber 48, whereby pressure differentials will be transmitted from the unit 2| to the indicating device causing diaphragm 49 to move toward the low pressure chamber 48. An arm 5| is secured to one end of the center of the diaphragm 49, and connected 'at the opposite end to a second arm 52, the latter passing through a sealing diaphragm 53 and rigidly secured to a U-shaped saddle member '54, which is pivotally secured to the housing 45 at 55, the axis of rotation of the saddle member lying substantially in the plane of the sealing 52 and saddle member 54 coacting as a unitary member so that the arm 52 pivots on the points 55. An indicatby tubing 23 with ing hand 55 is rotatably secured to the device, the hand rotating about the point 51, and a spring end, and secured at the opposite end to the adjacent end of the indicating hand. A link member 59 connects the hand 56 and an extension 6| of the saddle member 54, thus completing the assembly for transmittal of movement from the diaphragm to the indicating hand. While the present invention is illustrated in connection with the indicating device just described it will be apparent that any suitable instrument designed for use in systems having both high and low pressure sides may be utilized. Consequently, the particular indicating device illustrated does not constitute a part of the present invention other than in combination with the other elements of the system.

Installation of the device is as follows:

The foot is mounted on the hull of the boat substantially as shown in Fig. 1, the foot being preferably centrally positioned. The unit 2| is mounted in a vertical position and operatively connected with the foot by means of tubing 22 and 23. As previously mentioned, the unit 2| is preferably positioned at the normal water level so that upon opening of the ports 33 and 4|, the water will rise to the approximate level L. The indicating device 43 is mounted in the boat wherever desired and connected by means of tubing 44 and 45 to the unit 2|.

Upon movement of the boat in the direction of the arrow through the water, the resistance of the water to the passage through it of the foot I will result in an increased pressure of water at the opening I3 and a decreased pressure at opening I4, the action being substantially the same as that of the usual up and down stream Pitot tube. Increased pressure at the opening l3 will cause the water level in the chamber 24 to rise, compressing the air thereabove, while the decrease in pressure at the port M will cause the Water level in chamber 25 to lower due to the expansion of the air thereabove. The difierence in air pressures in 24 and 25 is transmitted through tubing 44 and 45 to chambers 41 and 48 of the indicating device where the increased pressure in chamber ti and reduced pressure in chamber 43 will cause the diaphragm 49 to move in the direction of chamber 48, the diaphragm movement in turn moving the arms 5| and 52, the latter rotating with the saddle member 54 about an axis passing through the plane of the sealing diaphragm 53. Movement of the saddle member 54 will move extension 6| thereof, which movement will be transmitted through link member 59 to indicating hand 55, causing the latter to pivot 51 until the applied pressures are balanced by the spring 58, thus indicating the differences in pressu two sides of the system which is proportional to the speed of the boat through the water, the dial of the indicator being graduated in miles per hour, etc. Should the system develop any leaks, etc., this will be readily apparent by examination of the transparent portions of the equalizing unit 2| which will disclose the water levels in the two chambers to be at different heights when the boat is at rest and the system under static pressure. Likewise, the gradual accumulation of air bubbles in the system will result in the levels of the water in the two chambers being at improper height when the-boat is at rest. The system can in such cases be returned to normal by unloosening the couplings 31', allowing air to enter or the chambers escape from the chamberswhereby thewater in use, the device being particularly adaptedfor :levels will be restored to normal, and in case of use on small boats or the like. v 'stoppage, etc., foreign matter may be blown from As illustrated in Figs. and 6, the device com .15 illustrated with concentric chambers, obviously lower ends of the tubing is a pressure foot desig- -it may be constructed of any suitable shape and nated generally by the numeral I and t0 the rate of flow of fluid in conduits or the like. This foot nd ap m mber I 64 form concentric -tions of the indicating device also being changed connected by a passageway with the chamto correspond to the particular units of measure- W- T foal? and Chambers 95 and 5 unit 2|. If the movement of the fluid in the ccnmm of s? device- Obviously any Pressure pressure of the fluid in the conduit 55, as the case ngidly secured by the shaft H 4 rotatably carried may be, will have no efiect whatsoever on the by the devicej member I is secured at readings or action of the indicating e. as one end to eirtenslon H6 0f the saddle member 54 of pressure due to waves, etc, as well as temperaat the opposite n to relatively fixed portion lation of the liquid pressures into air pressures. the bottom of the boat in any Suitable manner directly to the indicating device. As the areas any angl? Slope of the botmm of the hull the'tubes; etc, by compressed air orrcleaned by .prises a pair of concentric tubes MI and I0 2 0f other'suitable means. While the equalizing unit 5 metal or other suitable material. Secured to the ,1

relation to achievethe desired results. p s nds of the tubing is secured a cap The invention may also be used to measure the m m r 1' block 4 h tubing IUI and I is accomplished by merely substituting any of the Chambers and h foot is p v usual pressure diiierential generating devices for h a forwardly facing pe 0 P0 1 l 07 (Jonthe foot I, the remainder of the system being subnected W1th the chamber by a passageway stantially as that illustrated, the scale graduaand a rearwardly faclng Opening Port ment usecL Illustrated in Fig 4 is one form f function in the same manner as the foot I and having an orifice 56 of smaller area than that of 20 difiei'ential indicating strument designated chamber 25. 30

static pressures being substantially immaterial. secured to the bottgm of boat is a tu- It will also be noted that the indicating device bular Wen of SIZE to recelve the tube ml may be positioned as desired due to the trans- 50 and foot The wen may be secured to Consequently, it is immaterial at what hei ht as for example by the flange and screws above the equalizing unit in the indicatingde- The i l if desired" "F be constructed Vice is placed as the liquid is not transmitted to position the 'well I32 vertically regardless of on resting upon the upper end of the well I32 where by the device may be vertically adjusted with respect to the bottom of the boat.

The operation of the device is as follows:

length to extend above the normal water level n lc ng deVlCs If the llquld Was Ought well I 32, as shown in Figs. 5 and 6 and the plu s rectl to the indicator .1 I26 removed, whereupon the water will use into e device illustrated in Flgs. 5, and the chainbeis H15 nd I56, leaving an air space signedfol' use as speeid indicator on whom, at the top of each similar in manner to the unit constructed as a le integral unit which may that illustrated in Fig. ,1. A pressure will be be removably mounted in a boat so that it need formed at the port or opening I01 which will not remain on the boat when the latter is not cause a rise of water in the chamber I05, and

similarly, the lower pressure at the opening Hi9 will cause a lowering of the water level in the chamber I06, thereby causing an air pressure differential between the chambers I and I06. This air pressure differential is transmitted by tubing I22 and I24 and passageways I23 and I25 to the indicating device H2, where the pressure differential between the chambers 51 and 4B of said device will cause a movement of the diaphragm 49, and indicating hand I I3 through the connecting mechanism. When the boat is not in use, the device may be removed from the well I32 to a place of safe-keeping, thereby eliminating any possibility of theft or damaging of the instrument, while not in actual use. This construction likewise will not be afiected by temperatine changes or sudden change of water pressure due to waves, rocking of the boat, etc.

It will be apparent from the foregoing description that I have provided a measuring device of relatively simple construction, by means of which indications may be transmitted over distances by means other than the original liquid measured. Likewise, I have provided an indicating system which may be readily adapted for use as speed indicators for boats or the like, which is very efficient for such purposes, and which if desired may be constructed in the form of a portable unit that may be readily installed or removed from the boat. Furthermore, that I have provided novel means for equalizing and balancing both sides of the system when the latter is at static pressures, and by means of which leaks and other disturbances in the system may be readily detected.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit or scope of my invention; hence, I do not wish to limit myself to the exact construction, arrangement, and combination of parts herein shown and described or uses mentioned.

What I claim as new and desire to secure by Letters Patent is:

l. A differential indicating device for indicating the rate of flow of a fluid, comprising a pair of walled receptacles disposed in spaced relation with the walls of both forming one chamber and the wall of one a second chamber, closure means for sealing said chambers, a foot carried by at least one of said receptacles and adapted to be positioned in the fluid, said foot having oppositely disposed ports therein communicating with the respective chambers, a differential indicating unit carried by at least one of said receptacles at the end thereof opposite said foot, said indicating unit being operatively connected to the upper portions of the respective chambers.

2. A differential indicating device for indicating the rate of flow of a fluid, comprising a pair of concentric tubes connected at spaced points to form a pair of chambers, a foot carried by at least one of said tubes, adapted to be positioned in the fluid, said foot having opposite disposed ports therein communicating with the respective chamhers, a difierential indicating unit carried by at least one of said tubes at the end thereof opposite said foot, said indicating unit being operatively connected to th upper portions of the respective chambers, and means for selectively admitting air into or expelling air from said chambers.

3. A differential indicating device for indicating the rate of pair of concentric tubes connected at spaced points to form a pair of chambers, a foot, carried by at least one of said tubes, adapted to be positioned ports therein chambers, and a differential indicating unit carried by at least one of said tubes at the end thereof opposite said foot, said indicating unit being operatively connected to the upper portions of the respective chambers, the latter having vents therein for selectively admitting air into or expelling air from said chambers, and means for operatively mounting said device in an object, comprising a sleeve having one end thereof secured to the object and communicating with the fluid, the other end being positioned above the fluid level, said sleeve being of a size to receive said device with said foot extending therefrom into the fluid, and further means for supporting the device in said sleeve.

4. A difierential indicating device for indicating the rate of flow of a fluid, comprising a pair of concentric tubes, caps connecting the tubes at their ends to form a pair of chambers, a foot carried by one of said caps and adapted to be positioned in the fluid, said foot having oppositely disposed ports therein communicating with respective chambers, and a difierential indicating unit carried by another one of said caps, said indicating unit being operatively connected to the upper portions of the respective chambers, the latter having vents therein for selectively admitting air into or expelling air from said chambers, and means for operatively mounting said device in an object, comprising a sleeve having one end thereof secured to the object and communicating with the fluid, the other end being positioned above the fluid level, said sleeve being of a size to receive said device with said foot extending therefrom into the fluid, and further means for supporting the device in said sleeve.

5. In a differential speed indicating device for vessels, the combination of a pair of vertical concentric tubes, end members extending across respective ends of said tubes and secured thereto to form a pair of concentric chambers, the latter being positioned to intersect the water line of the vessel, said end members each having ports therein communicating with the respective chambers, a differential generating foot adapted to be positioned in the water below the vessel water line, said foot having oppositely disposed upstream and downstream ports therein, conduits connecting said upstream and downstream ports with respective ports in the lower end member, an air pressure differential indicating unit having high and low pressure sides, a conduit connecting the high pressure side of said indicating unit with the respective port in the upper end member communicating with the upstream port of said foot, another conduit connecting the low pressure side of said indicating unit with the other port in said upper end member, and means in said last mentioned end member for admitting air into or expelling air from the respective chambers, to bring the water levels therein substantially on the water line of the vessel.

CLAUDE L. ROBINSON. 

